The use of devices for mounting machine elements, such as pulleys and gears, upon a shaft is well-known.
One difficulty is that the known devices for mounting a machine element having a tapered bore upon a cylindrical shaft are cumbersome to use. For example, some devices require assembly of multiple pieces and adjustment of several screws, and other devices require modification of the shaft on which the machine element is mounted.
Another difficulty frequently encountered relates to the need for precise positioning of the machine elements at a fixed, axial position on the shaft when the machine element is mounted upon the shaft. This difficulty occurs when the mounting device is tightened and from a tendency of the machine element to slide axially along the tapered mounting surface due to the tapered bore of the machine element.